Olfaction plays a critical role in insect behaviors among agricultural pests and disease vectors. Hildebrand, et al., 1997, Annu. Rev. Neurosci, 20:595-631. Insect behavior is largely directed by the sensation of environmental olfactory cues (Gilliot C (2005) Entomology. 3rd Edition). The ability of an insect to respond to chemical stimuli is necessary for the insect to reproduce, mate, and feed. For example, insects respond to certain chemical stimuli by moving up a chemical gradient to identify and target a host.
This behavior contributes to the spread of diseases in humans, such as malaria, encephalitis, and dengue fever; as well as, animal and livestock diseases and can result in severe crop damage. More important to human health, the destructive behaviors of disease vector mosquitoes and related dipterans are driven by the sensory modality of olfaction, making it an important area of study (Carey A F, Carlson J R (2011) Proc Natl Acad Sci USA 108: 12987-12995). Mosquitoes, in particular, are believed to use olfaction to identify and target sources of bloodmeal for reproductive purposes.
The primary tool against insect borne diseases and crop damage due to insects is the use of insecticides that kill or repel the insect. However, each of the various forms of insecticide treatment—residual house spraying, crop dusting, insecticide treated clothes, bedding and netting, and chemical larviciding—have drawbacks, including environmental and host toxicity, limited duration and need for insect contact. Biological larviciding can avoid toxicity issues, but takes time and is quite expensive. Chemoprophylaxis is also expensive and may have unacceptable side effects. Finally, segregating populations is expensive and in many cases (third world countries) impractical.
Thus, while there are many different ways to attack insect pests, and each have contributed substantially to limiting the spread of disease and/or crop damage, they also each have limitations that leave room for substantial improvement. Despite advances in the field, there is still a scarcity of compounds that inhibit insect sensing. This need and other needs are satisfied by the present invention.